Piston lathe



Juiy 4 1933. c. 1.. EICH 199159193 PISTON LATHE F iled May 26, 1951 INVENTOR Patented July 4, 1933 4 UNITE CHARLES L. EICI-I, OF FRESNO, CALIFORNIA PISTON LATE-IE Application filed May as, 1931. Serial No. 549,044.

This invention relates to hand tools, my outer edges are cut so as to be disposed in V principal object being to provide a tool in shaped relation to each other. These plates the form of a portable hand-operated lathe form centralizing and locating guides for by means of which the lands of ring grooves the piston 7 to be worked on, and engage a in gas engine pistons may be cut back, the ring groove 8 of the piston. grooves may be widened or deepened as may On the same side of the bar 1 as that on be desired, or the piston undercut to allow which the guide plates 6 of the bar 2 are for drilling below the oil ring; it being unfixed, are vertically spaced guide and cutderstood that all operations are carried out ting elements 9 and 10, respectively. These separately and with the use of the proper are made of tool steel of rectangular or 50 tool element for the purpose mounted in the square section as usual, and are ground on lathe. one end so as to properly fit the groove being A further object of the invention is to pro- Worked on and function for the particular duce a simple and inexpensive device and operation to be performed.

15 yet one which will be exceedingly effective The elements Qand 10 extend parallel 130 for the purpose for which it is designed. the rods 3, and the element 10 is disposed so hese objects I accomplish by means of such that its cutting edge is in line with the line structure and relative arrangement of parts bisecting the angle between the outer edges as will fully appear by a perusal of the fol- I of the guides 6. Said cutting edge will 20 lowing specification and claims. therefore engage the groove at a point cen- In the drawing similar characters of reftrally between the points of engagement of erence indicate corresponding parts in the the guides 6 therewith. The guide element several views: 9 is above the cutting element relative to the Fig. 1 is an end view of my improved direction of rotation of the tool, and is 25 lathe, partly in section and operating on a ground on its outer end so as to smoothly piston to deepen a ring groove of the same. engage the bottom of the groove and also so Fig. 2 is a top plan view of the tool as in that it is the exact width of the groove. The operation. elements 9 and 10 abut against the side of Fig. 3 is a fragmentary end view of one the bar 1 and are mounted in slots S formed 30 of the bars showing the support for the cutin a block 11 rigidly secured against said bar. ter and the cooperating depth gage and guide Set screws 12 in the block bear against the member. elements and adjust-ably hold them in posi- Referring now more particularly to the tion. characters of reference on the drawing, the In operation the piston is clamped in a 35 lathe comprises a pair of parallel bars 1 and vise or chuck, and the handles are first un- 2. To the lower end of the bar 1, and the screwed so that the bars are spread suflicientupper end of the bar 2, the ends of rods 3 ly to enable them to straddle the piston. The of the same size and length are rigidly secutting element 10 is set so as to have a cercured. The rods are parallel to each other tain advance relative to the guide 9, and

0 and extend in opposite directions so as to the handles are then screwed up simultaneslidably pass through the lower and upper 'ously tobring the bars together, and so that ends of the bars 2 and 1, respectively. Outthe guides 6, and the elements 9 and 10, all ward of the bars the rods are both threaded engage the ring groove. The cutting eleand are engaged by handle sleeves 4 of the ment 10 is held against the metal with a pressame size and length, with stifi. compression sure sufficientto enable it to out by a screwsprings 5 between the handles and the ading up pressure exerted on the handles, which acent bars. places a yieldable pressure on the bars by Secured on one side of the bar 2 centrally reason of the springs 5 interposed therebe- I between the rods are thin plates 6 which protween. The handles are then grasped and ject in the direction of the bar 1 and whose pressure exerted thereon in a direction to rom0 tate the lathe about the piston for a full turn. If another cut is then necessary, the handles are again screwed up to restore the pressure on the spring and force the cutter deeper into the groove, and the tool is again rotated about the piston.

It will be noted that the member 9 serves as a depth gage for the cut as well as being a guide. Also, the cutter and guide are readily removed, so as to be interchangeable with others to fit various sizes of grooves.

It will also be noted that the bars,the rods, the springs and the handle sleeves are all purposely made the same size, so that manufacturing and assembling operations are simplified and cost held at a low figure.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention a set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described my invention what I claim as new and useful and desire to secure by Letters Patent is:

1. A hand lathe for cylindrical members comprising a pair of bars adapted to be disposed on opposite sides of a member for movement toward and from each other, parallel rods secured to the upper end of one bar and to the lower end of the other bar and slidably projecting thence in opposite directions through and beyond the corresponding opposite bars, a cutter on one bar for engagement with the member, and handle sleeves adjustably threaded on the rods beyond the bars whereby the latter may be rotated as a unit and adjusted toward and from each other.

2. A hand lathe for cylindrical members comprising a pair of bars adapted to be disposed on opposite sides movement toward and from each other, parallel rods secured to the upper end of one bar and to the lower end of the other bar and slidably projecting thence in opposite directions through and beyond the corresponding opposite bars, a cutter on one bar for engagement with the member and disposed substantially parallel to the rods, handle sleeves adjustably threaded on the rods beyond the bars, and compresslon springs on the rods between the inner ends of the sleeves and the ad acent bars.

In testimony whereof I aiiiX my signature.

CHARLES L. EICH.

of a member for 

